Air-Conditioning Loop Comprising A Devise For Receiving A Refrigerant

ABSTRACT

The subject of the invention is an air-conditioning loop ( 1 ) comprising a refrigerant circuit including at least one compressor ( 2 ), one external heat exchanger ( 11 ), one internal heat exchanger ( 5 ) or one refrigerant/heat transfer fluid exchanger ( 53 ), a device ( 16 ) for receiving the refrigerant, an expansion member ( 21 ) and an evaporator ( 24 ). The receiving device ( 16 ) comprises an inlet ( 17 ) coupled to the external heat exchanger ( 11 ), a first outlet ( 18 ) coupled to the expansion member ( 21 ) and a second outlet ( 19 ) coupled to a bypass device ( 28 ) for bypassing the evaporator ( 24 ).

The technical field of the present invention is that of reversible air-conditioning loops, otherwise called refrigeration loops or circuits. The invention is directed to such a loop intended to function at least in a so-called ‘heating’ mode and in a so-called ‘cooling’ mode.

An air-conditioning loop is classically used on automobile vehicles to generate an interior air flow at a required temperature and directed into the passenger compartment of the vehicle. The air-conditioning loop classically comprises an exterior heat exchanger, one or several expansion members, an evaporator, an accumulator and a compressor, through which a refrigerant travels in this order. The exterior heat exchanger is an exchanger through which passes an exterior air flow while the evaporator is an exchanger through which passes the interior air flow, i.e. the air flow intended to be distributed inside the passenger compartment of the automobile vehicle. The refrigerant circulating between an outlet of the compressor and an inlet of the expansion member is at a high pressure and a high temperature whereas the refrigerant circulating between the outlet of the expansion member and the inlet of the compressor is at a low pressure and a low temperature.

In the context of electrical or hybrid propulsion vehicles, it has been proposed to use the classic air-conditioning loop described above to heat or to cool the interior air flow intended to be distributed inside the passenger compartment. To do this, a supplementary exchanger and switching means enabling the circulation of the refrigerant in accordance with diverse circulation directions are integrated into the air-conditioning loop, the supplementary exchanger being placed in a heating, ventilation and/or air-conditioning installation enabling adjustment of the temperature of the interior air flow. The air-conditioning loop is then adapted to function in a so-called ‘heating’ mode, a so-called ‘cooling’ mode or a combined mode for drying the interior air flow.

In accordance with some embodiments, the accumulator is classically installed on the upstream side of the compressor in the direction of circulation of the refrigerant in the air-conditioning loop. Such an accumulator placed on the upstream side of the compressor does not allow heating of the refrigerant before its entry into the compressor.

However, in the case of high thermal loads, heating may be necessary to enhance the performance of the air-conditioning loop and to reduce its impact on fuel consumption.

Moreover, known air-conditioning loops do not allow the installation of an internal heat exchanger because its integration significantly degrades the efficiency of the air-conditioning loop when the latter is used in the so-called ‘heating’ mode.

The object of the present invention is thus to resolve the drawbacks described above mainly by modifying the architecture of the air-conditioning loop and the structure of the accumulator so that it is equally able to function as a storage cylinder. The modified accumulator thus becomes a device for receiving the refrigerant adapted to function in the so-called ‘heating’ mode or in the so-called ‘cooling’ mode and allowing heating of the refrigerant, for example in the case of high thermal loads. The device for receiving the refrigerant is placed in the high-pressure part of the air-conditioning loop in some modes and more particularly between the exterior heat exchanger and the expansion member.

Thus the invention consists in an air-conditioning loop comprising a refrigerant circuit including at least a compressor, an exterior heat exchanger, an interior heat exchanger or a refrigerant/heat-transfer fluid exchanger, a device for receiving the refrigerant, an expansion member and an evaporator. The receiving device more particularly comprises an inlet coupled to the exterior heat exchanger, a first outlet coupled to the expansion member and a second outlet coupled to a device for bypassing the evaporator.

In a first mode of operation of the air-conditioning loop, the so-called ‘heating’ mode, the refrigerant circulates successively in the compressor, the interior heat exchanger or the refrigerant/heat-exchange fluid exchanger, an expansion device, the exterior heat exchanger functioning as an evaporator, the inlet of the receiving device, the second outlet of the receiving device and the bypass device, before returning into the compressor.

The bypass device advantageously comprises a circulation duct coupled to an inlet of the compressor.

Moreover, a stop member commands the circulation of refrigerant in the bypass device, in particular in the circulation duct coupled to the inlet of the compressor.

In a complementary way, the air-conditioning loop comprises means for bypassing the interior heat exchanger or a refrigerant/heat-transfer fluid exchanger.

Arranged in this way, the air-conditioning loop is configured in accordance with a second mode, the so-called ‘cooling’ mode, in which the refrigerant circulates successively in the compressor, the bypass means, the exterior heat exchanger functioning as a condenser, the inlet of the receiving device, the first outlet of the receiving device, the expansion member and the evaporator, before returning into the compressor.

A stop member advantageously commands the circulation of refrigerant in the means for bypassing the interior heat exchanger or the refrigerant/heat-transfer fluid exchanger.

According to an additional feature, a first outlet of the expansion member is coupled to an inlet of the evaporator and an outlet of the evaporator is coupled to a second inlet of the expansion member.

In a complementary or optional manner, the air-conditioning loop includes an internal heat exchanger comprising a high-pressure part exchanging heat with a low-pressure part, the high-pressure part being installed between the first outlet of the receiving device and the expansion member and the low-pressure part being installed between the evaporator and the compressor.

The expansion member is preferably of the thermostatic or thermostatically controlled type.

In accordance with an alternative embodiment, the air-conditioning loop includes a heat-transfer fluid secondary circuit interacting with the refrigerant circuit via a refrigerant/heat-transfer fluid exchanger.

In this alternative configuration, the secondary circuit comprises a forced-air heater, allowing heating of the interior air flow, and means for circulating the heat-exchange fluid, such as a pump.

In accordance with one particular embodiment, the receiving device comprises a wall delimiting an internal volume defining a refrigerant separation space and a refrigerant storage space, the inlet and the second outlet of the receiving device opening into the separation space and the first outlet of the receiving device opening into the storage space.

The receiving device notably includes an extraction tube comprising a first part coupled to the second outlet of the receiving device, a second part comprising an end opening into the separation space and, in the storage space, a connecting portion, produced in particular in the form of an elbow, connecting the first part and the second part of the extraction tube.

A first advantage of the invention lies in the possibility of obtaining heating on the upstream side of the compressor, which makes it possible to maintain a high level of performance when the thermal load on the air-conditioning loop is high.

Another advantage lies in the possibility of integrating an internal heat exchanger without the latter having a negative impact on the performance of the air-conditioning loop when the latter functions in the so-called ‘heating’ mode.

Moreover, the present invention makes it possible to provide a device for receiving the refrigerant situated at the outlet of the exterior heat exchanger and functioning as:

-   -   an accumulator for storing the refrigerant and enabling         separation of the liquid phase and the gas phase of the         refrigerant when the exterior heat exchanger is operating as an         evaporator, or     -   a cylinder for storing, filtering and drying the refrigerant at         high pressure when the exterior heat exchanger is operating as a         condenser.

Other features and advantages of the invention will become apparent on examining the following description with reference to the appended drawings, which are provided by way of nonlimiting example and which may serve to complete the understanding of the present invention and the description of its implementation as well as, where necessary, to contribute to its definition, in which drawings:

FIG. 1 is a schematic view of an air-conditioning loop in accordance with the invention,

FIG. 2 is a schematic illustration of the refrigerant receiving device equipping the air-conditioning loop in accordance with the invention,

FIG. 3 is a schematic view of the air-conditioning loop in the so-called ‘cooling’ mode,

FIG. 4 is a schematic view of the air-conditioning loop in the so-called ‘cooling’ mode in accordance with a first variant of the invention,

FIG. 5 is a schematic view of the air-conditioning loop functioning in the so-called ‘heating’ mode, and

FIG. 6 is a schematic view of the air-conditioning loop in accordance with a second variant of the invention.

FIG. 1 is a schematic view of an air-conditioning loop 1 in accordance with the invention and shows one nonlimiting embodiment. FIG. 1 shows the positions of the components of the air-conditioning loop 1 relative to each other without prejudice as to the mode in which the air-conditioning loop is used.

A refrigerant circulates in a closed circuit in the air-conditioning loop 1. The refrigerant is circulated by a compressor 2 that receives the refrigerant at an aspiration temperature and at an aspiration pressure via an inlet 3, compresses it and then evacuates it via an outlet 4 at a discharge temperature and a discharge pressure higher than the aspiration temperature and the aspiration pressure.

The compressor 2 can be of the fixed or variable cubic capacity type and can be controlled internally, via a control valve or externally. The compressor 2 can equally be of the electric type.

The outlet 4 of the compressor 2 is coupled to a circulation duct conveying the refrigerant either to an interior heat exchanger 5 or to means 6 for bypassing the interior heat exchanger 5.

In accordance with another embodiment that is not shown, the air-conditioning loop 1 does not include any means 6 for bypassing the interior heat exchanger 5. The present invention is equally appropriate to this type of arrangement.

The refrigerant enters the interior heat exchanger 5 via an inlet 7 and leaves it via an outlet 8 after exchanging heat with a surrounding medium. In the FIG. 1 example, the surrounding medium is an interior air flow 31 that circulates inside a heating, ventilation and/or air-conditioning installation 9 of an automobile vehicle.

The interior heat exchanger 5 is adapted to allow exchange with the interior air flow 31 intended to be distributed inside the passenger compartment of the vehicle after it has passed through the heating, ventilation and/or air-conditioning installation 9. It is therefore an air/refrigerant exchanger intended for heat treatment, in particular heating, of the interior air flow 31 intended to be distributed inside the passenger compartment of the vehicle. In particular, the interior heat exchanger 5 is adapted to behave like a condenser that gives up to the interior air flow 31 heat resulting from the condensation of the refrigerant.

The outlet 8 of the interior heat exchanger 5 is coupled to a circulation duct that conveys the refrigerant to a first expansion device 10, more particularly to an inlet of the first expansion device 10.

The first expansion device 10 also comprises an outlet in fluid communication with a circulation duct that conveys the refrigerant to an exterior heat exchanger 11.

The exterior heat exchanger 11 is adapted to exchange heat with an exterior air flow 13 situated outside the passenger compartment of the vehicle. The exterior air flow 13 is preferably not intended to be distributed inside the passenger compartment of the vehicle. The exterior heat exchanger 11 is disposed at the front of a vehicle, for example.

The means 6 for bypassing the interior heat exchanger 5 comprise a circulation duct 44 having a refrigerant inlet 44 a arranged between the outlet 4 of the compressor 2 and the inlet 7 of the interior heat exchanger 5 and a refrigerant outlet 44 b arranged between the outlet 8 of the interior heat exchanger 5 and an inlet 12 of the exterior heat exchanger 11.

The refrigerant outlet 44 b is advantageously arranged between the outlet of the first expansion device 10 and the inlet 12 of the exterior heat exchanger 11.

The circulation of refrigerant inside the bypass means is made dependent on a first stop member 15. In accordance with one particular embodiment, the first stop member 15 takes the form of a control valve for opening or closing the circulation duct 44, allowing or preventing the circulation of the refrigerant in the circulation duct 44.

In accordance with a variant embodiment, the control valve is of the ‘binary’ type in that only two positions are allowed: fully open or fully closed. However, the first stop member 15 may equally consist in a control valve that opens and closes progressively.

Alternatively, the bypass means 6 is produced by a ‘three-way’ valve arranged at the refrigerant inlet 44 a or at the refrigerant outlet 44 b of the circulation duct 44. Arranged at the refrigerant inlet 44 a, the ‘three-way’ valve allows circulation of the refrigerant from the outlet 4 of the compressor 2 either to the inlet 7 of the interior heat exchanger 5 or to the refrigerant outlet 44 b of the circulation duct 44. Arranged at the refrigerant outlet 44 b, the ‘three-way’ valve allows the circulation of the refrigerant either from the outlet 8 of the interior heat exchanger 5, in particular the outlet of the expansion member, or from the refrigerant inlet 44 a of the circulation duct 44 to the inlet 12 of the exterior heat exchanger 11.

It is therefore clear that the first stop member 15 controls the circulation of the refrigerant in the circulation duct 44.

As the head loss inside the interior heat exchanger 5 is greater than the head loss in the bypass means 6, the refrigerant naturally bypasses the interior heat exchanger 5.

As defined with reference to FIG. 1, the bypass means 6 is therefore installed in parallel with the interior heat exchanger 5.

The exterior heat exchanger 11 also comprises an outlet orifice 14 through which the refrigerant is evacuated via a circulation duct to a device 16 for receiving the refrigerant.

The receiving device 16 stores, separates the liquid and gas phases of, filters and dries the refrigerant.

The refrigerant penetrates to the interior of the receiving device 16 via an inlet 17 and is able to leave it via a first outlet 18 and/or a second outlet as a function of the operating mode of the air-conditioning loop 1.

The first outlet 18 of the receiving device 16 enables refrigerant in the liquid state to exit to a first inlet 20 of an expansion member 21 via a circulation duct. The expansion member 21 can be a second expansion device 21 that can be similar to the first expansion device 10. The expansion member 21 or the second expansion device 21 is advantageously a thermostatic expansion member.

The second expansion device 21 includes a first outlet 22 coupled to an inlet 23 of an evaporator 24.

The refrigerant is expanded on passing through the second expansion device 21 between the first inlet 20 and the first outlet 22. The pressure of the refrigerant at the inlet 23 of the evaporator 24 is therefore lower than the pressure of the refrigerant on the upstream side of the first inlet 20 of the expansion member 21 in the direction of flow of the refrigerant.

The evaporator 24 is installed inside the heating, ventilation and/or air-conditioning installation 9 so that the interior air flow 31 passes through it and it exchanges heat therewith. The evaporator 24 cools the interior air flow 31 before it is distributed inside the passenger compartment of the vehicle.

The temperature of the interior air flow 31 is adjusted before distribution inside the passenger compartment of the vehicle by mixing the interior air flow 31 that has passed through the evaporator 24 and/or the interior heat exchanger 5.

The refrigerant circulates inside the evaporator 24 and leaves it via an outlet 25 before entering the second expansion device 21 via a second inlet 26. The second expansion device 21 finally comprises a second outlet coupled to the inlet 3 of the compressor 2 via a circulation duct.

The expansion member 21 or the second expansion device 21 is preferably a thermostatically controlled expansion member or thermostatic expander so that the degree of opening, and thus the expansion of the refrigerant in the second expansion device 21, is controlled by the heating of the refrigerant at the outlet of the evaporator 24.

Alternatively, the second expansion device 21 may be produced in the form of a tube orifice arranged between the first outlet 22 of the receiving device 16 and the inlet 23 of the evaporator 24.

A device 28 for bypassing the evaporator 24 is arranged between the second outlet 19 of the receiving device 16 and the inlet 3 of the compressor 2. The bypass device 28 is installed in parallel with at least the evaporator 4 and the second expansion device 21.

In accordance with a complementary variant that will be described with reference to FIG. 4, the bypass device 28 is also installed in parallel with an internal heat exchanger.

The bypass device 28 is constituted of a circulation duct 29 through which the refrigerant circulates. The circulation of refrigerant inside the bypass device 28 is dependent on a second stop member 30. In accordance with one particular embodiment, the second stop member takes the form of a control valve for opening or closing the circulation duct 29, allowing or preventing the circulation of the refrigerant in the circulation duct 29.

In accordance with a variant embodiment, the control valve is of the ‘binary’ type in that it has only two positions: completely open or completely closed. However, the second stop member 30 may equally consist in a control valve that opens and closes progressively.

Alternatively, the bypass means 30 is produced by a ‘three-way’ valve arranged between the receiving device 16, the second expansion device 21 and the compressor 2.

It is therefore clear that the second device 30 controls or commands the circulation of the refrigerant in the circulation duct 29. The head loss in the circuit part constituted by the second expansion device and the evaporator 24 being greater than the head loss in the bypass device 28, the refrigerant naturally circulates via the circulation duct 29 rather than through the evaporator 24.

The evaporator 24 is installed in the heating, ventilation and/or air-conditioning installation 9 so that the interior air flow 31 passes through it.

The circulation of the interior air flow 31 through the interior heat exchanger 5 is commanded by a first flap constituting a control flap 62, arranged on the upstream side of the heat exchanger in the direction of circulation of the interior air flow 31, and a second flap constituting a mixing flap 63, disposed on the downstream side of the interior heat exchanger 5 in the direction of circulation of the interior air flow 31.

In accordance with an alternative embodiment, it is possible to envisage disposing a single mixing flap arranged on the upstream or downstream side of the interior heat exchanger 5 in the direction of circulation of the interior air flow 31.

FIG. 2 is a diagrammatic illustration of the refrigerant receiving device 16 equipping the air-conditioning loop 1 according to the invention. The receiving device 16 comprises a wall 32 delimiting an internal volume 33. The wall 32 preferably takes the general form of a hollow cylinder closed by a bottom 34 closing the lower part of the receiving device 16 and a cover 35 shutting off the upper part of the receiving device 16.

The bottom 34 of the receiving device 16 advantageously has a concave shape so as to accommodate the refrigerant FR. The internal volume 33 of the refrigerant receiving device 16 is for example between 150 cm³ and 1500 cm³, in particular equal to 1000 cm³.

The inlet 17 of the receiving device 16 is produced through the cover 35 and is coupled to an admission tube 36 terminating inside the internal volume 33 at an admission opening 37, in particular a lateral aperture 37.

The first outlet 18 of the receiving device 16 is formed through the bottom 34, in particular at the lowest point of the bottom 34. In any event, the first outlet 18 must be placed at a location on the wall 32 where refrigerant in the liquid phase can be aspirated.

The second outlet 19 is produced through the cover 35 and constitutes a first end of an extraction tube 38. The extraction tube 38 comprises a rectilinear first part 39 coupled to a connecting portion 40, in particular produced in the form of an elbow 40 forming a 180° arc. The extraction tube 38 further comprises a rectilinear second part 41 coupled to the elbow 40 and terminating at a second end 42. The second end 42 opens into the internal volume 33 of the upper part of the receiving device 16.

The elbow 40 comprises a capture hole 64 installed at the level of the point of inflection of the 180° arc formed by the elbow 40. The capture hole 64 enables oil capture in order to feed the air-conditioning loop 1. The capture hole 64 is furnished with a filtration member 65.

The internal volume 33 of the receiving device 16 is divided into at least two spaces. Immediately adjacent the cover 35 there is a refrigerant separation space 43 a and immediately adjacent the bottom 34 there is a refrigerant storage space 43 b.

The operation of the receiving device 16 will now be described. The refrigerant enters the receiving device 16 via the inlet 17 and circulates in the admission tube 36. The refrigerant then enters the internal volume 33 via the admission opening 37 in a two-phase state, namely a mixture of liquid and gas.

As a function of the mode of operation of the air-conditioning loop 1, the refrigerant enters the receiving device 16 either at low pressure or at high pressure.

The liquid phase of the refrigerant descends by gravity along the wall 32 and accumulates in the storage space 43 b whereas the gas phase of the refrigerant remains in the upper part of the internal volume 33.

As a function of the mode of operation of the air-conditioning loop 1, the refrigerant leaves the receiving device 16 either in the liquid state via the first outlet 18 or in the gas state via the second outlet 19.

The air-conditioning loop according to the invention is able to function in at least three modes: a so-called ‘heating’ mode in which the interior heat exchanger 5 heats the interior air flow 31 intended to be distributed inside the passenger compartment, a so-called ‘cooling’ mode in which the evaporator 24 cools the interior air flow 31 intended to be distributed inside the passenger compartment and a so-called ‘mixed’ or ‘drying’ mode in which the interior air flow is cooled and dried by the evaporator 24 before being heated by the interior heat exchanger 5 before being distributed inside the passenger compartment. An additional, so-called ‘de-icing’ mode may also be envisaged for de-icing the exterior heat exchanger 11.

FIG. 3 illustrates the so-called ‘cooling’ mode of operation of the air-conditioning loop 1. The refrigerant is circulated by the compressor 2. The first stop member 15 is in an open position allowing the circulation of the refrigerant through the circulation pipe 44. The circulation of the refrigerant through the interior heat exchanger 5 is prevented or low, even quasi-zero.

The refrigerant circulation duct arranged between the inlet 44 a of the bypass means 6 and the inlet 7 of the interior heat exchanger 5 and the refrigerant circulation duct arranged between the outlet 8 of the interior heat exchanger 5 and the outlet 44 b of the bypass means 6 are represented in dashed line to illustrate the absence of circulation or the low circulation of refrigerant.

Thereafter, after the outlet 44 b of the bypass means 6, the refrigerant passes through the exterior heat exchanger 11 to enter the receiving device 16 via the inlet 17. In this so-called ‘cooling’ mode, the second stop member 30 is in a closed position preventing circulation or allowing low circulation of the refrigerant in the bypass device 28. The absence of circulation or the low circulation of refrigerant in the bypass device 28 is shown in dashed line.

In this configuration, refrigerant in the liquid phase is captured by the first outlet 18 of the receiving device 16 and then circulates toward the second expansion device 21.

After it has been expanded, the refrigerant passes through the evaporator 24 and cools the interior air flow 31 by exchange of heat. The cycle terminates with the return of the refrigerant to the compressor 2.

The so-called ‘cooling’ mode of operation utilizes the refrigerant in the liquid phase in the receiving device 16. It is thus possible to have refrigerant in the pure liquid phase permanently at the inlet of the second expansion device 21 and to obtain efficient cooling tending to maximize the thermodynamic efficiency of the air-conditioning loop 1 in the case of high thermal loads.

FIG. 4 is a schematic view of the air-conditioning loop 1 in accordance with a first variant of the invention in the so-called ‘cooling’ mode. Refer to the description of FIGS. 1 and 3 for the identical elements.

The refrigerant circulating between the outlet 4 of the compressor 2 and the first inlet 20 of the second expansion device 21 is at a high pressure and a high temperature whereas the refrigerant circulating between the first outlet 22 of the second expansion device 21 and the inlet 3 of the compressor 2 is at a low pressure and a low temperature.

Such an air-conditioning loop can be improved by the addition of an internal heat exchanger 45 the function of which is to create a thermal exchange between the refrigerant at high pressure/high temperature and the refrigerant at low pressure/low temperature.

The internal heat exchanger 45 comprises a high-pressure part 46 exchanging heat with a low-pressure part 47.

The internal heat exchanger 45 comprises a high-pressure inlet 48 coupled to the first outlet 18 of the receiving device 16 and a high-pressure outlet 49 coupled by a circulation duct to the first inlet 20 of the second expansion device 21. The high-pressure inlet 48 and the high-pressure outlet 49 of the internal heat exchanger 45 both communicate with the high-pressure part 46 of the internal heat exchanger 45.

The internal heat exchanger 45 also comprises a low-pressure inlet 50 coupled to the second outlet 27 of the second expansion device 21 and a low-pressure outlet 51 coupled to the inlet 3 of the compressor 2. The low-pressure inlet 50 and the low-pressure outlet 51 both communicate with the low-pressure part 47 of the internal heat exchanger 45.

In the so-called ‘cooling’ mode, the refrigerant flows through the internal heat exchanger 45, which thus serves to increase the efficiency of the air-conditioning loop 1.

FIG. 5 is a schematic view of an air-conditioning loop 1 operating in the so-called ‘heating’ mode.

In this configuration, the internal heat exchanger 45 is represented as optional, because the air-conditioning loop 1 in accordance with the invention is able to function with no internal heat exchanger.

In the so-called ‘heating’ mode shown in FIG. 5, the refrigerant is circulated by the compressor 2. The first stop member 15 is in a closed position preventing circulation or allowing a low circulation of the refrigerant through the circulation duct 44 and allowing circulation of the refrigerant through the interior heat exchanger 5. The circulation duct 44 in represented in dashed line to illustrate low or no circulation of refrigerant.

The refrigerant thus circulates in the direction of the interior heat exchanger 5. An exchange of heat is then created between the interior air flow 31 and the refrigerant circulating in the interior heat exchanger 5. The refrigerant is then expanded by means of the first expansion device 10, the pressure of the refrigerant on the downstream side of the first expansion device 10 in the direction of circulation of the refrigerant being lower than the pressure of the refrigerant on the upstream side of the first expansion device 10.

Thereafter the refrigerant passes through the exterior heat exchanger 11 to enter the receiving device 16 via the inlet 17. In the so-called ‘heating’ mode, the second stop member 30 is in an open position allowing circulation of the refrigerant in the bypass device 28.

The refrigerant in the gas phase is captured by the second outlet 19 of the receiving device 16 by means of the extraction tube 38. The refrigerant then circulates directly to the inlet 3 of the compressor 2 and thus bypasses the second expansion device 21 and the evaporator 24.

The absence of circulation of the refrigerant through the second expansion device 21 and through the evaporator 24 is illustrated in dashed line in FIG. 5.

It will be noted in particular that the internal heat exchanger 45 is also bypassed thanks to allowing circulation of refrigerant in the bypass device 28. It is thus seen that the internal heat exchanger 45 is inactive, which eliminates the negative impact that it has when a refrigerant flows through the latter in the so-called ‘heating’ mode.

Alternatively, a greater or lesser circulation of refrigerant through the second expansion device 21 and through the evaporator 24 can also be produced in order to provide an additional mode of operation, such as the so-called ‘mixed’ or ‘drying’ mode.

FIG. 6 is a schematic view of the air-conditioning loop 1 in accordance with a second variant of the invention. In this example, the air-conditioning loop 1 is shown in the so-called ‘heating’ mode. For the identical elements, refer to the description of the preceding figures.

According to this variant embodiment, the interior heat exchanger 5 is replaced by a refrigerant/heat-transfer fluid exchanger 53 arranged in the air-conditioning loop 1. The refrigerant/heat-transfer fluid exchanger 53 is also arranged in a secondary circuit 52 in which a heat-transfer fluid circulates. The secondary circuit 52 also includes a forced-air heater 54 mounted in the heating, ventilation and/or air-conditioning installation 9.

According to the second variant of the invention shown in FIG. 6, the air-conditioning loop 1 thus includes a refrigerant circuit and a heat-transfer fluid secondary circuit 52 interacting with each other via the refrigerant/heat-transfer fluid exchanger 53.

The refrigerant/heat-transfer fluid exchanger 53 enables an exchange of heat between the refrigerant circuit and the secondary circuit 52. The secondary circuit 52 thus has a function of transferring heat exchanged with the refrigerant circuit in the interior heat exchanger 53 to the forced-air heater 54.

The heat-transfer fluid is advantageously water to which glycol has been added, for example.

The refrigerant/heat-transfer fluid exchanger 53 has a first circuit 55 forming a refrigerant circuit that exchanges heat with a second circuit 56 forming a heat-transfer fluid circuit.

The second circuit 56 forming a heat-transfer fluid circuit communicates with the refrigerant/heat-transfer fluid exchanger 53 via an inlet 60 and an outlet 61.

Circulation means 57, in particular a pump 57, is placed in fluid communication with the second circuit forming a heat-transfer fluid circuit of the refrigerant/heat-transfer fluid exchanger 53 via a circulation duct. The circulation means 57 circulate the heat-transfer fluid inside the secondary circuit 52 so as to transfer heat exchanged inside the refrigerant/heat-transfer fluid exchanger 53 to the forced-air heater 54.

The forced-air heater 54 comprises an inlet 58 coupled to an outlet of the circulation means 57. The forced-air heater 54 comprises an outlet 59 coupled to the inlet 60 of the second circuit 56 forming a heat-transfer fluid circuit of the refrigerant/heat-transfer fluid exchanger 53.

When the air-conditioning loop 1 operates in the so-called ‘heating’ mode, the refrigerant passing through the first circuit 55 forming a refrigerant circuit of the refrigerant/heat-transfer fluid exchanger 53 exchanges heat with the second circuit 56 forming a heat-transfer fluid circuit of the refrigerant/heat-transfer fluid exchanger 53. The circulation means 57 circulate the heat-transfer fluid to the forced-air heater 53 that enables an exchange of heat between the heat-transfer fluid and the interior air flow 31 passing through the heating, ventilation and/or air-conditioning installation 9.

In the so-called ‘cooling’ mode, the circulation means 57 is stopped in order to prevent any circulation of heat-transfer fluid in the forced-air heater 53.

The second variant of the invention shown in FIG. 6 is a so-called ‘indirect’ configuration because the interior air flow 31 exchanges heat indirectly with the refrigerant circuit of the air-conditioning loop 1 via the heat-transfer fluid circulating in the secondary circuit 52.

The configurations shown in FIGS. 1 and 3 to 5 are called ‘direct’ because the air-conditioning loop 1 exchanges heat directly with the interior air flow 31 via the interior heat exchanger 5.

The second or so-called ‘indirect’ variant of the invention shown in FIG. 6 avoids the placement of a component at high pressure in the heating, ventilation and/or air-conditioning installation 9.

Although shown in the so-called ‘heating’ mode in FIG. 6, the so-called ‘indirect’ configuration is equally compatible with the so-called ‘cooling’ mode as shown in FIG. 3 or 4.

The air-conditioning loop 1 exploits the use of the same component, i.e. the receiving device 16, that assumes the function of a storage cylinder when the air-conditioning loop functions in the so-called ‘cooling’ mode and assumes the separation and accumulation function of an accumulator when the air-conditioning loop functions in the so-called ‘heating’ mode.

In accordance with an alternative embodiment, having the bypass means 6 and the bypass device 28 arranged so as to enable circulation of the refrigerant in the evaporator 24 and the interior heat exchanger 5 or the refrigerant/heat-transfer fluid exchanger 53 in order to provide the ‘drying’ mode may be envisaged.

Obviously, the invention is not limited to the embodiments described above and provided by way of example only. It encompasses diverse modifications, alternative forms and other variants that the person skilled in the art might envisage within the framework of the present invention and notably all combinations of the various embodiments described above. 

1. An air-conditioning loop (1) comprising a refrigerant circuit including at least a compressor (2), an exterior heat exchanger (11), an interior heat exchanger (5) or a refrigerant/heat-transfer fluid exchanger (53), a receiving device (16) for receiving the refrigerant, an expansion member (21) and an evaporator (24), wherein the receiving device (16) comprises an inlet (17) coupled to the exterior heat exchanger (11), a first outlet (18) coupled to the expansion member (21), and a second outlet (19) coupled to a bypass device (28) for bypassing the evaporator (24).
 2. An air-conditioning loop (1) as claimed in claim 1, wherein the bypass device (28) comprises a circulation duct (29) coupled to an inlet (3) of the compressor (2).
 3. An air-conditioning loop (1) as claimed in claim 1, wherein a stop member (30) commands the circulation of refrigerant in the bypass device (28).
 4. An air-conditioning loop (1) as claimed in claim 1, wherein the air-conditioning loop (1) comprises bypass means (6) for bypassing the interior heat exchanger (5) or a refrigerant/heat-transfer fluid exchanger (53).
 5. An air-conditioning loop (1) as claimed in claim 4, wherein a stop member (15) commands the circulation of refrigerant in the bypass means (6) for bypassing the interior heat exchanger (5) or the refrigerant/heat-transfer fluid exchanger (53).
 6. An air-conditioning loop (1) as claimed in claim 1, wherein the air-conditioning loop (1) is configured in accordance with a heating mode in which the refrigerant circulates successively in the compressor (2), the interior heat exchanger (5) or the refrigerant/heat-transfer fluid exchanger (53), an expansion device (10), the exterior heat exchanger (11), the inlet (17) of the receiving device (16), the second outlet (19) of the receiving device (16), and the bypass device (28) before returning into the compressor (2).
 7. An air-conditioning loop (1) as claimed in claim 1, wherein the air-conditioning loop (1) is configured in accordance with a cooling mode in which the refrigerant circulates successively in the compressor (2), the bypass means (6), the exterior heat exchanger (11), the inlet (17) of the receiving device (16), the first outlet (18) of the receiving device (16), the expansion member (21), and the evaporator (24) before returning into the compressor (2).
 8. An air-conditioning loop (1) as claimed in claim 1, wherein a first outlet (22) of the expansion member (21) is coupled to an inlet (23) of the evaporator (24), and an outlet (25) of the evaporator (24) is coupled to a second inlet (26) of the expansion member (21).
 9. An air-conditioning loop (1) as claimed in claim 1, wherein the air-conditioning loop (1) includes an internal heat exchanger (45) comprising a high-pressure circuit (46) exchanging heat with a low-pressure circuit (47), the high-pressure circuit (46) being installed between the first outlet (18) of the receiving device (16) and the expansion member (21), and the low-pressure circuit (47) being installed between the evaporator (24) and the compressor (2).
 10. An air-conditioning loop (1) as claimed in claim 1, wherein the expansion member (21) is thermostatically controlled.
 11. An air-conditioning loop (1) as claimed in claim 1, wherein the air-conditioning loop (1) includes a heat-transfer fluid secondary circuit (52) interacting with the refrigerant circuit via a refrigerant/heat-transfer fluid exchanger (53).
 12. An air-conditioning loop (1) as claimed in claim 11, wherein the secondary circuit (52) comprises a forced-air heater (53) and a pump (57).
 13. An air-conditioning loop (1) as claimed in claim 1, wherein the receiving device (16) comprises a wall (32) delimiting an internal volume (33) defining a refrigerant separation space (43 a) and a refrigerant storage space (43 b), the inlet (17) and the second outlet (19) of the receiving device (16) opening into the separation space (43 a), and the first outlet (18) of the receiving device (16) opening into the storage space (43 b).
 14. An air-conditioning loop (1) as claimed in claim 13, wherein the receiving device (16) includes an extraction tube (38) comprising a first part (39) coupled to the second outlet (19) of the receiving device (16), a second part (41) comprising an end (42) opening into the separation space (43 a) and, in the storage space (43 b), a connecting portion (40) connecting the first part (39) and the second part (41) of the extraction tube (38).
 15. An air-conditioning loop (1) as claimed in claim 2, wherein a stop member (30) commands the circulation of refrigerant in the bypass device (28).
 16. An air-conditioning loop (1) as claimed in claim 2, wherein the air-conditioning loop (1) comprises bypass means (6) for bypassing the interior heat exchanger (5) or a refrigerant/heat-transfer fluid exchanger (53).
 17. An air-conditioning loop (1) as claimed in claim 3, wherein the air-conditioning loop (1) comprises bypass means (6) for bypassing the interior heat exchanger (5) or a refrigerant/heat-transfer fluid exchanger (53). 